the heat is ...um not going to be needed for a little while

Our energy bill nearly doubles in the winter. Summertime not so bad, we have central air, but only run it a couple times a year on the odd chance we have company over during a heat spell. New fridge and stove (one died the day after thanksgiving and left us with a ton of leftovers slowly warming, and the other shorted out one day while my brother was cooking and irreparably destroyed my favorite stoneware brownie pan) all of our non-dimmable lights are cfl's, generally our electric consumption is pretty low, and on a general downward trend.

The gas bill is another story. Our drier is fantstic, barely budges the needle, and in the summer it gets used less. Furnace? UGGH! We changed out the old manual mercury needle with a digital timer that automatically follows a preset series of temps for weekdays and weekends. Never above 64 degrees. In fact it spends more time in the dormant mode where actual indoor temps range from 55-60 degrees. But as I said, the gas bill doubles our monthly energy cost at what I consider to be moderate conservation (because of a having a baby in the house who was born at risk we really cant go much lower).

The furnace that came with the house was built with the house, making about 21 years old. I'm sure this is a huge part of it. But part of the home improvement vision is adding some manner of fireplace upstairs. Having visited a friend with a woodstove I witnessed firsthand how powerfull even a small one can be. A couple of sticks and the living room was toasty in about 20 minutes. I'd like a woodstove, I like the idea of renewable sunshine as opposed to tapping ancient sunshine we can't get back. I don't know too much about the wherefore's and why's of woodstoves, nor how much it will cost to put in. Any suggestions?